i dont know if all of them are yellow but i do know that they have stickers on them mabey for recording purposes. like seeing how a certain panel absorbs the impact or something like that. mabey the gurus can clarify

In any floor shops (manufacturing, grading, testing, etc ) places all the moving parts are marked in yellow. for example fork lifts, platform vehicles, towing lanes, etc are marked in yellow to symbolize that they are moving object and to avoid being close to it.

the crash test cars are moving objects in the floor shop and hence painted in yellow

my thoughts: Yellow colour has better visibility, hence moving parts/vehicles get yellow paint. Also recollect that yellow colour is used on almost all cabs across the world for same reason of better visibility.

my thoughts: Yellow colour has better visibility, hence moving parts/vehicles get yellow paint. Also recollect that yellow colour is used on almost all cabs across the world for same reason of better visibility.

Going a little off topic

You are correct " The color (and name) yellow was selected by John Hertz as the result of a survey by the University of Chicago which indicated it was the easiest color to spot."

The Stickers on the test cars are basically "Track-points" and "Tracking-Sensors",after the test is done they use differet softwares eg.like Boujou,where they put the entire scene-shoot from Digi-beta tape,the track-points are read by the software which helps in creating virtual camera for softwares like 3ds max,maya,cinema-4d etc,which acts like a real capture shoot in 3D enviornment,then the Tracking-sensors are imported in the 3d scene,and rigged/merdged to the 3D car model,where they get to learn the behavior of the car at the collision.

The same technique we also use for Green-screen shoots where we put real people and real objects in the 3D enviornment created by me.Hope my statement cleares some of the doubts,any film/Ad-makers here can corect me if i am going wrong somewhere,as this is my personl working experience..cheers

Ramie

Edit:there is no specific reason for why yellow colour is used,ive seen even black,orange,silver colours car crash testing on youtube videos